Medermycin Inhibits TNFα-Promoted Inflammatory Reaction in Human Synovial Fibroblasts.

Synovial inflammation plays a crucial role in the destruction of joints and the experience of pain in osteoarthritis (OA). Emerging evidence suggests that certain antibiotic agents and their derivatives possess anti-inflammatory properties. Medermycin (MED) has been identified as a potent antibiotic, specifically active against Gram-positive bacteria. In this study, we aimed to investigate the impact of MED on TNFα-induced inflammatory reactions in a synovial cell line, SW-982, as well as primary human synovial fibroblasts (HSF) using RNA sequencing, rtRT-PCR, ELISA, and western blotting. Through the analysis of differentially expressed genes (DEGs), we identified a total of 1478 significantly upregulated genes in SW-982 cells stimulated with TNFα compared to the vehicle control. Among these upregulated genes, MED treatment led to a reduction in 1167 genes, including those encoding proinflammatory cytokines such as IL1B, IL6, and IL8. Pathway analysis revealed the enrichment of DEGs in the TNF and NFκB signaling pathway, further supporting the involvement of MED in modulating inflammatory responses. Subsequent experiments demonstrated that MED inhibited the expression of IL6 and IL8 at both the mRNA and protein levels in both SW982 cells and HSF. Additionally, MED treatment resulted in a reduction in p65 phosphorylation in both cell types, indicating its inhibitory effect on NFκB activation. Interestingly, MED also inhibited Akt phosphorylation in SW982 cells, but not in HSF. Overall, our findings suggest that MED suppresses TNFα-mediated inflammatory cytokine production and p65 phosphorylation. These results highlight the potential therapeutic value of MED in managing inflammatory conditions in OA. Further investigations utilizing articular chondrocytes and animal models of OA may provide valuable insights into the therapeutic potential of MED for this disease.

Mild inflammation persists in the glenohumeral joint of patients with shoulder instability: Cross-sectional study.

Objective: Approximately two-thirds of patients with history of shoulder dislocation may develop osteoarthritis (OA) of the glenohumeral joint. However, the biochemical mechanisms underlying the association between dislocation and OA are largely unknown. This study aimed to investigate macrophage markers and inflammatory cytokine expression associated with shoulder instability (SI) in comparison to rotator cuff tears (RCTs). Design: This study included 30 patients with SI and 30 patients with RCTs. Synovial membrane samples were harvested from the rotator interval during the arthroscopic anatomical repair for both groups. The localization of tumor necrosis factor-α (TNF-α), interleukin (IL)-1ß, and cluster of differentiation (CD) 68 in synovial membranes was determined by immunohistochemistry. Transcript-level expressions of the inflammatory cytokines (TNFA and IL1B) and macrophage markers pan-CD68 and -M1 (CD80 and CD86) were quantified. CD80 and CD86 expression in macrophages from the SI group was confirmed using flow cytometry. Results: TNF-α, IL-1ß, and CD68 were expressed in the synovial lining layer of the synovial tissue in both groups. In addition, the mRNA expressions of TNFA, IL1B, CD68, and CD80 were significantly higher in the SI group compared to the RCT group (P â€‹= â€‹0.012, 0.014, 0.022, 0.003, respectively). In samples from the SI group, 96.3% of CD68+/CD14+ macrophages were CD86-positive, whereas 2.5% of CD68+/CD14+/CD86+ cells were CD80-positive. Conclusions: Patients with SI had higher mRNA levels of TNFA, IL1B, CD68, and CD80 than those with RCTs. These findings may partially explain the biochemical mechanism underlying the frequent development and progression of osteoarthritis in patients with SI.

ß2-Microglobulin Elevates COL5A1 mRNA in the Subsynovial Connective Tissue of Patients Receiving Hemodialysis With Carpal Tunnel Syndrome.

Background Although carpal tunnel syndrome (CTS) is frequently observed in patients undergoing long-term hemodialysis (HD), exactly how CTS arises is unknown. Here, we examined levels of COL5A1 in the subsynovial connective tissue (SSCT) of patients receiving HD and studied its potential regulation by ß2-microglobulin (Β2-MG) in SSCT-derived cells (SSCTCs). Methods We extracted SSCT samples from 67 patients with CTS (49 non-HD and 18 HD) during carpal tunnel release. The samples were subjected to quantitative polymerase chain reaction (qPCR) to determine COL5A1 expression. Further, to examine the potential regulation of COL5A1 expression by Β2-MG, SSCTCs were stimulated in the absence (control) or presence of 10 µg/ml Β2-MG. Results The HD group showed significantly elevated COL5A1 levels compared to the non-HD group (P=0.027). Moreover, treating SSCTCs with Β2-MG for 24 h increased the mRNA expression of COL5A1 relative to control conditions (P=0.013). Conclusions Elevated COL5A1 expression may form part of the mechanism underlying the development of CTS, and Β2-MG may play a role in promoting COL5A1 expression in HD patients.

The Relationship Between Falling Distance and Trauma Severity Among Fall Injury Survivors Who Were Transported to a Trauma Center.

Introduction Falls from >6 meters have been shown to cause multiple traumas and serious injuries. However, especially among fall survivors who were transported to trauma centers, the relationship between falling distance and trauma severity remains unclear. This study aimed to investigate the relationship between falling distance and trauma severity among fall injury survivors who were transported to a trauma center and clarify the characteristics of trauma among survivors of falls from high places from an orthopedic surgeon's perspective. Methods We retrospectively reviewed the medical records of 65 fall injury survivors who were transported to a trauma center for falling distance; whether the fall was a suicide attempt; abdominal, chest, and head trauma; the numbers of upper-limb, lower-limb, and spinal vertebral fractures; McCormack load-sharing classification score; unstable pelvic fracture; Frankel classification; injury severity score (ISS); and duration of intensive care unit (ICU) and hospital stay. We evaluated the correlations between falling distance and the other factors and compared all factors between those falling <6 meters and those falling >6 meters. Results Falling distance was weakly positively correlated with durations of ICU and hospital stay. The percentage of cases that were suicide attempts, the number of lower-limb fractures, the McCormack load-sharing classification score, and the durations of ICU and hospital stay were significantly higher among those falling from >6 meters than among those falling from <6 meters. Conversely, there were no significant differences in abdominal trauma, chest trauma, head trauma, number of upper-limb fractures, number of vertebral fractures, unstable pelvic fracture, or Frankel classification between the two groups. Conclusion The findings indicate that falling from a higher distance may increase lower-limb and vertebral fracture severity and may lead to longer ICU and hospital stays among fall injury survivors who are transported to trauma centers.

Elevation of MMP1 and ADAMTS5 mRNA expression in glenohumeral synovia of patients with hypercholesterolemia.

BACKGROUND: Epidemiological studies have reported a positive association between hypercholesterolemia and shoulder disease. Previous studies have focused on the effect of hypercholesterolemia on tendinopathy. Moreover, hypercholesterolemia has also been linked to joint pathology in the knee and hand. However, the effect of hyperlipidemia on glenohumeral joint remain unclear. A hypercholesterolemic condition has been reported to alter levels of A Disintegrin and Metalloprotease with Thrombospondin Motifs (ADAMTSs) and matrix metalloproteases (MMPs) in synovium of the knee joint. Here, we evaluated the mRNA expression of ADAMTSs and MMPs in the glenohumeral synovium of patients with and without hypercholesterolemia. METHODS: Study participants were 73 patients who underwent arthroscopic rotator cuff repair for degenerative rotator cuff tears. They were divided into two groups according to total cholesterol (TC) and triglyceride levels. Synovial membrane samples were harvested at the rotator interval during surgery, and mRNA expression levels of the aggrecanases ADAM-TS4 and ADAM-TS5 and MMPs (MMP-1, 3, 9, and 13) were analyzed quantitatively. RESULTS: ADAM-TS5 and MMP1 mRNA levels were significantly higher in the high TC group than in the low TC group (P = 0.023 and P = 0.025, respectively). In contrast, no significant differences were observed in ADAMTS4 or MMPs 3, 9, and 13 (ADAMTS4, P = 0.547; MMP3, P = 0.55; MMP9, P = 0.521; and MMP13, P = 0.785). CONCLUSION: Hypercholesterolemia may alter MMP1 and ADAMTS5 expression in the synovium of the glenohumeral joint.

ß2-microglobulin alters the profiles of inflammatory cytokines and of matrix metalloprotease in macrophages derived from the osteoarthritic synovium.

Several studies have implicated ß2-microglobulin (B2M) in osteoarthritis (OA) pathology. Of the main constituents of synovial tissue, synovial fibroblasts and macrophages, the latter play a pivotal role in inflammation. Although several studies have investigated the effects of B2M on synovial fibroblasts, few have examined the impact on synovial macrophages. Here, we investigated the effect of B2M on the expression profiles of inflammatory cytokines and matrix metalloproteases (MMPs) in synovial macrophages. Synovial macrophages were isolated from the osteoarthritic synovium using an anti-CD14 anti- body and magnetic isolation system. Synovial macrophages were stimulated with B2M for 6 and 24 h. Following stimulation, cell surface marker (CD80, CD163, CD206), cytokine [interleukin (IL)-6, IL-8, tumor necrosis factor α (TNF-α)] and matrix metalloprotease (MMP; MMP-9 and MMP-13) genes were evaluated by real-time PCR. Additionally, cytokine concentrations in cell culture supernatant were determined using enzyme-linked immunosorbent assay (ELISA). B2M significantly increased CD80 and decreased CD163 expression. In addition, B2M stimulation increased inflammatory cytokines at both the mRNA and protein levels. While B2M likewise elevated MMP-13 levels, there was no difference in MMP-9 expression between vehicle and B2M-treated cells. B2M increased M1 macrophage marker, inflammatory cytokine, and MMP-13 expression in synovial macrophages. B2M-related activation of synovial macrophages may thus be associated with OA pathology.

Jietacin Derivative Inhibits TNF-α-Mediated Inflammatory Cytokines Production via Suppression of the NF-κB Pathway in Synovial Cells.

Synovial inflammation plays a central role in joint destruction and pain in osteoarthritis (OA). The NF-κB pathway plays an important role in the inflammatory process and is activated in OA. A previous study reported that a jietacin derivative (JD), (Z)-2-(8-oxodec-9-yn-1-yl)-1-vinyldiazene 1-oxide, suppressed the nuclear translocation of NF-κB in a range of cancer cell lines. However, the effect of JD in synovial cells and the exact mechanism of JD as an NF-κB inhibitor remain to be determined. We investigated the effect of JD on TNF-α-induced inflammatory reaction in a synovial cell line, SW982 and human primary synovial fibroblasts (hPSFs). Additionally, we examined phosphorylated levels of p65 and p38 and expression of importin α3 and ß1 using Western blotting. RNA-Seq analysis revealed that JD suppressed TNF-α-induced differential expression: among 204 genes significantly differentially expressed between vehicle and TNF-α-stimulated SW982 (183 upregulated and 21 downregulated) (FC ≥ 2, Q < 0.05), expression of 130 upregulated genes, including inflammatory cytokines (IL1A, IL1B, IL6, IL8) and chemokines (CCL2, CCL3, CCL5, CCL20, CXCL9, 10, 11), was decreased by JD treatment and that of 14 downregulated genes was increased. KEGG pathway analysis showed that DEGs were increased in the cytokine−cytokine receptor interaction, TNF signaling pathway, NF-κB signaling pathway, and rheumatoid arthritis. JD inhibited IL1B, IL6 and IL8 mRNA expression and IL-6 and IL-8 protein production in both SW982 and hPSFs. JD also suppressed p65 phosphorylation in both SW982 and hPSFs. In contrast, JD did not alter p38 phosphorylation. JD may inhibit TNF-α-mediated inflammatory cytokine production via suppression of p65 phosphorylation in both SW982 and hPSFs. Our results suggest that JD may have therapeutic potential for OA due to its anti-inflammatory action through selective suppression of the NF-κB pathway on synovial cells.

Increasing transforming growth factor-beta concentrations with age decrease apelin in the rat rotator cuff.

BACKGROUND: The rotator cuff undergoes natural degeneration with age, leading to age-related rotator cuff tear; however, the precise mechanism remains unclear. Transforming growth factor-beta (TGF-ß) concentrations rise with age and TGF-ß contributes to the pathophysiology of skeletal muscle. TGF-ß has also been shown to suppress expression of the myokine, apelin, in skin fibroblasts. We hypothesized that TGF-ß expression in the rotator cuff changes with age and regulates apelin expression, thereby contributing to rotator cuff degeneration. METHODS: We used quantitative reverse-transcription polymerase chain reaction (Q-RT-PCR) to measure the expression of apelin and tendon-related genes (Tnmd, Col1a1, and Col3a1) in the rotator cuff of young (12 weeks), adult (24 weeks), and old (48 weeks) rats. Using Q-RT-PCR and enzyme-linked immunosorbent assay, we also measured Tgfb mRNA and TGF-ß protein levels, respectively. Furthermore, we used Q-RT-PCR to measure apelin mRNA levels in rotator cuff-derived cells after treatment with 0 (control) and 10 ng/mL recombinant TGF-ß. RESULTS: Apelin mRNA levels were significantly lower in old compared to young and adult rats. Similarly, tendon-related genes, Tnmd, Col1a1, and Col3a1, were significantly lower in adult and old rats than young rats. In contrast, Tgfb mRNA and TGF-ß protein were significantly higher in old compared to young rats. Stimulation with exogenous TGF-ß significantly decreased Apelin mRNA expression compared to control. CONCLUSIONS: TGF-ß regulates apelin expression in the rotator cuff and may play a key role in the degenerative pathology of the rotator cuff with age.

Limitation of the external glenohumeral joint rotation is associated with subacromial impingement syndrome, especially pain.

BACKGROUND: Subacromial impingement syndrome is a common disorder associated with functional impairment and disability of the shoulder. Internal/external glenohumeral rotation is important for shoulder function. However, because it is difficult to measure the glenohumeral joint rotation angle physically, the relationship between this angle and the clinical symptoms of subacromial impingement syndrome is still largely unknown. Using advanced cine-magnetic resonance imaging techniques, we designed a study to improve our understanding of the nature of this relationship. METHODS: We evaluated 100 shoulders with subacromial impingement syndrome. Patients underwent cine-magnetic resonance imaging during axial rotation with the arm adducted. During imaging, patients rotated their shoulder from maximum internal rotation to maximum external rotation over 10 seconds and then to maximum internal rotation over 10 seconds. The rotation angles were then evaluated using a series of axial images. The Constant-Murley (Constant) and UCLA scores for each patient were determined, and the correlation between the scores and rotational angles was assessed. Patients were divided into 3 groups according to the Constant pain score, and the rotational angles of each group were compared. Rotational angles were also compared between shoulders with and without night pain. RESULTS: The external rotation angle showed a significant but low correlation with the Constant and UCLA scores (ρ = 0.24 and 0.24, respectively), whereas the internal rotation angle did not. In comparing the pain groups of Constant score and UCLA score, the external rotation angle significantly decreased as pain increased (P < .01), demonstrating a negative correlation (ρ = -0.47, -0.41, respectively). Additionally, the shoulders of patients with night pain showed significantly more restriction of external rotation angles than the shoulders of those without night pain (P = .01). CONCLUSIONS: Limitation of the glenohumeral joint's external rotation is correlated with pain, for which we explore possible explanations. The results suggest that night pain can be effectively reduced using therapeutic interventions that target external rotational dysfunction.

Poly(POG)n loaded with recombinant human bone morphogenetic protein-2 accelerates new bone formation in a critical-sized bone defect mouse model.

BACKGROUND: Delivery of bone morphogenetic protein-2 (BMP-2) via animal-derived absorbable collagen materials is used for the treatment of large bone defects. However, the administration of bovine proteins to humans is associated with the risk of zoonotic complications. We therefore examined the effect of combining BMP-2 with collagen-like peptides, poly(POG)n, in a critical-sized bone defect mouse model. METHODS: A 2-mm critical-sized bone defect was created in the femur of 9-week-old male C57/BL6J mice. Mice were randomly allocated into one of four treatment groups (n = 6 each): control (no treatment), poly(POG)n only, 0.2 µg, or 2.0 µg BMP-2 with poly(POG)n. New bone formation was monitored using soft X-ray radiographs, and bone formation at the bone defect site was examined using micro-computed tomography and histological examination at 4 weeks after surgery. RESULTS: Administration of 2.0 µg of BMP-2 with poly(POG)n promoted new bone formation and resulted in greater bone volume and bone mineral content than that observed in the control group and successfully achieved consolidation. In contrast, bone formation in all other groups was scarce. CONCLUSIONS: Our findings suggest the potential of BMP-2 with poly(POG)n as a material, free from animal-derived collagen, for the treatment of large bone defects.